package registry

import (
	"os"
	"path/filepath"
	"testing"
)

func TestSnapshotToProducesOpenableCopy(t *testing.T) {
	dir := t.TempDir()
	reg, err := Open(filepath.Join(dir, "registry.db"))
	if err != nil {
		t.Fatal(err)
	}
	defer reg.Close()
	if err := reg.Upsert(Route{Host: "a.example.com", Kind: "service", Addr: "10.0.0.1:3000", Status: "ready"}); err != nil {
		t.Fatal(err)
	}

	out := filepath.Join(dir, "snap.db")
	if err := reg.SnapshotTo(out); err != nil {
		t.Fatal(err)
	}

	copyReg, err := Open(out)
	if err != nil {
		t.Fatalf("open snapshot: %v", err)
	}
	defer copyReg.Close()
	rt, err := copyReg.Get("a.example.com")
	if err != nil {
		t.Fatal(err)
	}
	if rt.Addr != "10.0.0.1:3000" {
		t.Fatalf("snapshot route addr = %q, want 10.0.0.1:3000", rt.Addr)
	}
}

func TestSnapshotToRefusesExistingTarget(t *testing.T) {
	dir := t.TempDir()
	reg, err := Open(filepath.Join(dir, "registry.db"))
	if err != nil {
		t.Fatal(err)
	}
	defer reg.Close()
	out := filepath.Join(dir, "snap.db")
	if err := os.WriteFile(out, []byte("x"), 0o644); err != nil {
		t.Fatal(err)
	}
	if err := reg.SnapshotTo(out); err == nil {
		t.Fatal("SnapshotTo over an existing file: want error, got nil")
	}
}